A wireless ad hoc network is a decentralized type of network. In comparison to infrastructure-based wireless networks, ad hoc networks are self-forming wireless networks which can operate in the absence of any fixed infrastructure, and in some cases an ad hoc network is formed entirely of mobile units. An ad hoc network typically includes a number of geographically-distributed, potentially mobile units, sometimes referred to as “nodes,” which are wirelessly connected to each other by one or more links (e.g., radio frequency communication channels). The nodes can communicate with each other over a wireless media without the support of an infrastructure-based or wired network. In addition, the nodes in a wireless ad hoc network typically transmit “beacons.” A beacon (for example, a beacon frame) contains information about the network and is typically broadcast periodically to announce the presence of the network to nodes that may wish to join the network.
Wireless ad hoc networks are beneficially implemented to provide communication mechanisms for emergency services such as police, fire, and others at the site of an emergency or at a similar incident site. For instance, natural disasters can cause extensive damages to land-based telecommunication infrastructures. In such circumstances, wireless ad hoc networks can be substituted to provide messaging capabilities for both the rescuers and the victims. Such a wireless ad hoc network can, for example, be part of an incident area network. When nodes in incident area networks actively participate in forwarding routing requests and providing beacons, 1) network overhead and 2) power usage may be increased. Increased network overhead has an impact on the ability to transmit, for example, voice and data messages because bandwidth is used to transmit management information (for example, beacons) rather than messages. Increased power usage can have a negative impact on battery life and many nodes in a wireless ad hoc network are often battery powered. Many existing techniques and protocols cannot address these two issues when ad-hoc wireless networks have a large number of nodes, very mobile nodes, dynamic node memberships, or a combination of these characteristics.
Accordingly, there is a need for intelligent and dynamic selection of beacon transmitting nodes in wireless ad hoc networks.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.